Pattern



April 9, 1929. J DU -i- 1,708,568

PATTERN Filed Oct. 25, 1926 INVENTOR Jfl Du/Vo/v 7" ATTORNEY Patented Apr. 9, 1929.

EDEN D. DU MONT, 0F ALAMEDA, CALIFORNIA.

PATTERN.

Application filed October 25, 1926. Serial No. 143,898.

The pr sent invention relates to improvements in pattern used for molding sand to provide a-form for casting metal or the like. My invention has particularreference to a pattern of the base member of a chimney which may be briefly described as a cast iron plate formed with a ring on one side over which the chimney fits and formed with a central hole thru which soot, ashes, etc. may be removed from the chimney, a gate being provided on the opposite face of the chimney base for closing the opening. This gate is made slidable and requires for its support two guides which are undercut in the confronting faces to provide grooves in which the gate isslidably received and supported. The present invention is particularly concerned with the undercut guides which cannot be permanently fixed to the pattern on account or" their undercut which would break up the molding sand when the pattern is removed therefrom. F or this reason, it has been customary to provide small removable guides which would stick to the molding sand when the pattern is removed and were formed so as to allow of careful removal from the molding sand thereafter. This, however, is a tedious process and consumes considerable time.

The object of the present invention is to provide a more convenient means for providing the guide cavities in the molding sand and I utilize for this purpose disappearing guides made in such a manner that they can be manipulated from the side of the pattern and made to disappear into the pattern by a revolving motion while the molding sand is still in place on the pattern and without disturbing the molding sand. Further objects and advantages of my invention will appear as the specification proceeds.

The preferred form of my invention is illustrated in the accompanying drawing in which Figure 1 shows a side view of my pattern as confined between the two sections of a mold commonly known as the drag and the cope,

Figure 2 is a plan view of the pattern,

Figure 3 a bottom plan view of the pattern,

And Figure l an enlar ed sectional detail view taken along lines l1 of Figure 3.

While I have shown only the preferred form of the invention, I wish to have it understood that various changes or modifications may be made within the scope of the claims hereto attached without departing from the spirit of the invention.

My pattern comprises the wood plate I having the upper face section of the pattern 2 secured to one side and the bottom face section to the other side. The former is of conven tional form and offers no novel features. The bottom face section comprises the two projecting guides 3 arranged in confronting relation as shown in sembles in cross section a fragmentary cylinder and is pivoted within the plate 1 by means of an axial rod t in such a manner that the guide may be swung into the plate so as to completely disappear therein or may be projected upwardly into a position where its front face 6 inclines inwardly in the direction of the other guide and is adapted for cooperation with the latter in supporting a gate slid between the guides from the diverging ends thereof. The two guides are operated by means of handles 7 arranged parallel to one of the side edges of the plate so that the guioes may be operated at any time and without disturbing molding sand lying against the face of the pattern. The manner of using my invention is very simple. The two mold sections 8 and 9 are clamped upon the pattern in any suitable manner as, for instance, by bolts extending thru ears 11 projecting from the end of the pattern. Molding sand is then introduced into one of the mold sections and tamped to make perfect contact with the pattern. The section first filled is then covered by means of a board and the entire device turned upside down whereupon the second section is filled with molding sand and tamped. If the mold sections were now removed from the pattern without attention given to the guides 3, the undercut in the latter would break up the molding face of the sand and destroy the same. To avoid this, it is only necessary to manipulate the handles 7 whereby the two guides 6 are made to disappear into the plate and allow the molds to be removed without any difficulty. To provide sharper lines and a good support for the guides 3, a metal plate 12 may be embedded in the wooden plate 1 so as to be flush with the surface thereof and bearing elements 13 may be fastened to the under face of the metal plate for supporting the axial rod of the guides 3.

I claim:

1. A pattern of the character described Figure 3. Each guide recomprising a Wooden board having a metal plate embedded in one face thereofso as to be substantially flush therewith, bearing elemerits secured to the bottom of the plate, and a molding elei'nent pivoted in the bearing and. formed for projection beyond the face of the 1 metal plate and for Withdrawal thereinto. 1

2. In a pattern for a chimney base casting,

a pattern board havingoppositely;disposed; recesses therein, an undercut projection dis- ,posedineachrecess, said projection extend ing beyond thexfaee iotithe. boardi adjacent: to i thGiHIOl'Cl material, and being designedin the shapeIof a. fractional cylinder so a's;t0- move on the arc of a circle, and means rotatablv supported in said board and extending outside of theiboardffor rotatingsaidiprojectioni posed i 3.- Ina'pattern for-a chimney base casting having undercut guidesat the-oppositeedges 1 thereof, afpatternbeard-having recesses therein adjacent to the positions-of said un- "dercutguides, projection rotatablydis- I in eachfrecess andbeing formed in the shape of a fractional cylinder; an axial rod secured; to each projection for swinging-the same; bearings inside. of said boardton rotat- 7 ably supporting said rods in theboard, said rodsiextending outside of 'saidboard so as to be manually rotated for withdrawing said projections from the undercut position.

i v 4, Inapattern for a casting having undercut members at the opposite edges thereof, a

pattern board having recesses therein adjacent to the positions of said undercut ineinbers,--aplateeinbeddedrin the recessed face of the board said plate having elongated apertures-above said recesses bearings depending froin 'said plate intosaid boar-d; projecoutsideotsaid board soas toperinit thewithdraWaLot said pro ections frorntheundercut position.

In test-nnony whereofl do hereby'aiiiX' mysignature.-

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